SP: Default Value For Output Parameters

When I call a proc with one input parameter and two output parameters, (all the three parameters having defaults in the proc), I was expecting to see these values defaulted to in the proc. But apparently, this not the case. Could someone tell me what am I doing wrong here? Appreciate your time.

USE Pubs
GO

CREATE PROCEDURE dbo.MyTestProc
(@InputParamVARCHAR(30) = 'Input',
@OutPutParam1VARCHAR(30) = 'OutputParam1' OUTPUT,
@OutPutParam2VARCHAR(30) = 'OuputParam2' OUTPUT)
AS
BEGIN
SELECT @InputParam, @OutPutParam1, @OutPutParam2
END
GO

-- Call to the proc
USE Pubs
GO

DECLARE @I1VARCHAR(30)
DECLARE @P1VARCHAR(30)
DECLARE @P2VARCHAR(30)

SET@I1 = 'PassedInput'


EXECdbo.MyTestProc
@I1,
@P1 OUTPUT,
@P2 OUTPUT

SELECT@I1, @P1, @P2

EXEC dbo.MyTestProc